Temperature indicator for internal combustion engines



Feb. 16, 1932. w, 5, JARVIS 1,845,049

TEMPERATURE INDICATOR FOR INTERNAL COMBUSTION ENGINES Filed July 12 1925 IN VEJVTUR W/W/am 5. Jars u I Patented Feb. 16, 1932 UNITED STATES PATENT OFFICE mm 3. JARVIS, OF GRAND RAPIDS, MICHIGAN, ASSIGNOB 10 W. 3. JARVIS COI- rm, OF GRAND RAPIDS, MICHIGAN INDICATOR FOB. INTERNAL COMBUSTION GENTS Application filed July 12, 1928. Serial No. 122,024.

The main objects of this invention are:

First, to provide an improved temperature indicator for internal combustion engines in which the signal or indicating means, such as lamps, are located upon the dash.

Second, to provide an improved temperature indicator of the class described which may be adjusted or calibrated to the articular engine or make of engines upon w ich it is to be used for indicating desirable runnir llghconditions.

ird, to provide an apparatus having these advantages which is very reliable and eflicient and at the same time economical in structure.

Objects relating to details and economies of construction and operation of my invention will definitel appear from the detailed descri tion to fbllow.

The invention is clearly defined and pointed out in the claim.

A structure which is a preferred embodiment of my invention is illustrated in the ac companying drawings, forming a part of this ap lication, in which:

ig: 1 is a front elevation of the signal unit of my improved temperature indicator, a fragment of the dash being shown to illustrate its relation thereto.

Fig. 2 is a detail vertical section through the lamp housing on a line corresponding to line 2-2 of Fig. 1.

Fi 3 is a fragmentary vertical section of the t ermostatic-unit on a line corresponding to line 33 of Fig. 4, a fragment of the water jacket of an internal combustion engine being shown to illustrate the operative relation of the thermostatic unit thereto, the electrical connections for the thermostatic and signal units of Figs. 2 and 3 being diagrammatically indicated in these figures.

Fig. 4 is a fragmentary view partially in section of a thermostatic unit, the cap thereof being removed.

Fig. 5 is a rear view of the signal unit.

Fig. 6 is a fragmentary front elevation of a modified form of signal unit.

In the drawings similar reference characters refer-to similar parts throughout the several views.

Referring to the drawings, 1 represents the wall of the watergacket of an internal combustion engine an 2 the dash or instrument board of an automobile.

I will first describe the signal unit which, in its preferred embodiment as shown in Figs. 1 and 2, comprises a cast metal housing 3 having a reduced threaded neck 4 which is inserted through an opening 5 in the dash 2. The window 6 which may be of glass, celluloid or other suitable material is secured upon the end of the neck by means of the flanged collar 7, a gasket 8 bein arranged between the inner end of this col ar and the dash 2.

The clamping nut 9 is threaded upon the neck, a spring washer or gasket 10 being arran ed between the nut and the dash 2 so that the ousing is effectively clamped and supported upon the dash.

The housing has an internal shoulder 11 at its rear end, the rear wall'12 being seated upon this shoulder and supported thereon by means of the split ring 13 which is engaged in the groove 14 at the rear of the shoulder. This rear wall 12 carries a plurality of lamp sockets 15, there being thnee sockets in the structure illustrated for the lamps 16, 17 and 18, these lamps being of different colors, as red, green and amber as indicated.

The wall 12 carries binding posts 19 for these lamps and also a binding post 20 which is connected to the electrical connection 21 to the ignition control switch, conventionally shown at 22.

In the modification shown in Fig. 6, the lam'p housing indicated at 24 is provided with. partitions 25, providing a plurality of compartments 26 in which the lamps are arran ed, the compartments having a window 2 The thermostat unit comprises a plug-like casing 28 threaded at 29so that it may be threaded into a hole 30 tapped into the wall of the water jacket or to the body of an internal combustion engine. This casing is closed at its inner end but is subject to the water within the cooling system where it projects into the water chamber, as illustrated.

Within this casing I mount a pair of ther-" mostatic elements 31 and 32, these being mounted on the bottom of the casing in the structure illustrated.

At the outer end of the casing is an insulating ring 33 carrying tubular hollow holders 34: for the contacts 35, 36 and 37. These contact holders also constitute binding posts for the lamp connecting wires.

The contacts 35 and 36 are arranged in 0pposed relation to coact with the thermostatic element 31 while the contact 37 is arranged to coact with the thermostatic element 32. The contact 36 is connected toithe green lamp 17 by means of the wire 38 while the contact 35 is connected to'the red lamp by means of the wire 39, the contact 37 being connected to the amber-colored lamp by means of the wire 40.

' It will be observed that the thermostatic 20 elements are grounded through the casing to the wall of the engine or its water jacket,

the thermostatic elements constitutin in effect, switches closing the circuits t rough the difierent lamps.

In the embodiment illustrated, the thermostatic element 31 is in contact normally, or when the engine is cold, with the contact 36 so that when the ignition control switch 22 is closed the green lamp is lighted, thus indicating that the engine is cold. When the temperatures rises to a predetermined point, this contact is broken.

At another predetermined temperature, the

thermostatic element 32 engages the contact 35 37, thus turning on the amber lamp. This may be adjusted as desired to indicate low running conditions or the approach to the danger point. The thermostatic element 31 enga es the contact 35 at such point, closing D the circuit of the red lamp.

It will be understood, of course, that any selected colors ma be used. Further, the contacts may be a justed so as to operate at redetermined points to turn ofi the green 4 amp, for instance, or red or the amber, and

the temperature at which the signal is to be given;

It is well understood that the temperature at which highest efiiciency results, varies in 5 different engines or makes of engines and my improved apparatus enables the adjustment to meet varying views or conditions.

While I have illustrated and described the use of lamps, other signal units may be employed, as sounding si als or a combination of lamps and sounding si als. Further, while I prefer to use the t ree signals, as illustrated the number of signals ma be varied as desired, an apparatus having t ree si als having proved very desirable.

.l have illustrated and described my imrovements in an embodiment which I have ound very practical. I have not attempted ure made will enable those skilled in the art to embody or adapt my improvements as may be desire Having thus described my invention, what I claim as new and desire to secure by Letters Patent, is: v

A thermostat device comprising a pair of thermostatic members disposed in parallel relation within a casing, the planes of movement of said thermostatic element being transverse to each other, a pair of opposed adjustable contacts operatively associated with one of said thermostatic elements, such element being normally engageable with one of said contacts, and a third adjustable contact o eratively associated with the other of said t ermostatic elements.

In witness whereof I have hereunto set my hand.

. WILLIAM B. JARVIS. 

